Screen Cast has two methods to create a connection to your PC, Mac, Linux desktops and other devices.

The lag problem may be related to your Wi-Fi network speed. The best option is to turn on your phone's hotspot. Connect your PC or other device to your phones mobile hotspot. Then edit the application settings and select the connection type as Mobile Hotspot.

Once you have configured the settings, you will be able to view your mobile screen to PC without any lag.